1. Field of the Invention
The present invention relates to a cover member of an airbag device in which a plurality of door portions cleaved at the time of inflation and expansion of an airbag are segmented in a cover body covering the airbag.
2. Description of the Related Art
Conventionally, there has been used an airbag device provided in a fixed portion of a steering wheel of a vehicle such as an automobile. Such an airbag device includes an airbag substantially shaped like a bag, an inflator for supplying gas to the airbag, and a cover member for covering and accommodating the airbag at the time of non-expansion. In the cover member, a cover body covering the airbag accommodated in a retracted state is formed with a tear line (a breaking scheduled portion) that is easily broken. For example, configuration is such that when a vehicle receives an impact due to a collision or the like, gas is supplied to the airbag from the inflator to inflate the airbag, the cover body of the cover member is broken along the tear line due to the inflation of the airbag to form a plurality of door portions, and the door portions are expanded about hinge portions, so that the airbag is expanded toward an occupant side and thus an occupant is constrained and protected.
For such a cover member of an airbag device, there has been known a configuration in which an emblem (an ornament) as an ornamental member is mounted on approximately the center of the cover member and a tear line is disposed along the emblem. In this configuration, a fixing pin protruding from a back side of an emblem body disposed at a surface side of a cover body is inserted through the cover body, and a locking portion protruding from the tip end of the fixing pin is fitted into and locked into a through hole as a lock receiving portion provided to a mounting member disposed at a back side of the cover body, so that the cover body is sandwiched between the emblem body and the mounting member and the emblem is fixed (for example, refer to Japanese Laid-open Patent Application No. 2000-255361 (pages 3 and 4 and FIGS. 1 to 3)).
Since the door portion mounted with the emblem is heavier than a door portion having no emblem, the start of expansion behavior may be delayed. Furthermore, if the expansion starts once, the door portion has a tendency to move in the same direction due to large inertia. Therefore, the shape of the door portion mounted with the emblem is allowed to be different from that of the door portion having no emblem and the area of the door portion mounted with the emblem is allowed to be larger than that of the door portion having no emblem, so that the door portion mounted with the emblem is more largely affected by force when an airbag is expanded as compared with the other door portions, and is expanded with good balance without delay with respect to other door portions (for example, refer to Japanese Laid-open Patent Application No. 2009-166780 (pages 4 and 5 and FIG. 1)).
However, since the locking portion of the fixing pin is firmly fitted into the through hole in order to allow the emblem to be reliably held in the door portion against the centrifugal force applied at the time of expansion of the door portion, workability at the time of the fitting may deteriorate and productivity and manufacturability may deteriorate.